Why some people hear 'yanny' and some hear 'laurel'

TomoNews US - May 18, 2018

THE INTERNET — An audio clip saying either the word "yanny" or "laurel" has gone viral over social media.
The short audio clip originated on Vocabulary.com under the word "laurel," and was traced back to a Flowery Branch High School freshman in Georgia on May 11, who posted the audio clip to her Instagram story, according to Wired.
The sound clip was then posted by YouTuber Cloe Feldman onto Twitter where it took off.
A possible explanation why people are hearing different words is because the file is "acoustically ambiguous" or very poor-quality, according to Northwestern University neurobiology professor Nina Kraus.
The clip that went viral had already been re-recorded several times, meaning there were multiple steps that degraded the quality of the audio.
According to Brad Story, professor of speech, language and hearing sciences at the University of Arizona, the two words also have similar sound patterns.
This combined with the low quality of the sound file could account for the different things people hear.
The pitch of the clip can also affect what is heard.

In general, people heard "yanny" more consistently when the pitch was lower and "laurel" when the pitch was higher..